[minulache]

Originally Posted by wheela

The boost you're achieving on 1+ seems pretty normal. That 12-ish psi you're getting at 6500rpm isn't bad for the stock turbo, I get similar on stage 2+. WGDC% is kinda high up there, but that could be due to high ambient temp (less dense air, turbo has to work harder to make boost, and needs more boost to hit load% request).

I alway suspected I had a bit of a boostleak due to stft% going negative on pulls like you. But I recently replaced my injectors and rail pressure sensor and that doesn't really happen any more.

I will try today to clean the MAF sensor and check the O2 Sensors and see from there. Regarding the boost target vs actual it is better now for sure, but I am curious to why on Virtual Dyno it shows only 10 whp more on stage 1+ compared to stock
Mods are: chargepipe and next week FMIC

[wheela]

Not sure about the virtual dyno numbers, but I can say that when I went from stock to stage 1 I couldn't really feel a difference. The biggest bump in performance that I could actually tell a difference was getting my catless downpipe.

[Malteser_wfj]

Originally Posted by minulache

So also the gasket that leads from the inlet pipe to the turbo is gone, tested today. Ordered the gaskets and gonna give it another try with all the new gaskets to see where the leaks lead me )

Originally Posted by minulache

Update, also the gasket on the boost pressure sensor in the CP was done. Changing also that.

What was the part number for the gasket on the pressure sensor? I can't find one for it on RealOEM.

Did you then do 15 and 29 as there doesn't seem to be a gasket coming from the compressor for the tube into the intercooler?

I've already replaced 17 and 19 and have the VRSF chargepipe.

Is it worth replacing anything else upstream of the turbo like the one for the MAF sensor 3?


This is what I'm using for reference on a 03/2012 UK N55 on 124k miles https://www.realoem.com/bmw/enUS/sho...diagId=13_1357

I'm going to take it into a shop next week for shifter bushes and diff fluid change and they're going to diagnose it too. Is it worth preparing for the fact that the turbo to intercooler pipe could have a crack or even the turbo inlet?

[minulache]

Today I changed the gaskets from the intercooler and from the turbo outlet to intercooler and now it's holding boost as it should for a PWG, so problem solved
Malteser_wfj , for the pressure sensor I used a gasket from a set, Inner diameter of 9mm and thickness of 2mm.
I did 15 and 29 from that diagram and also today I changed the turbo outlet to intercooler gasket with 11618506782, I couldn't find it in the diagram and just ordered this one to try and it worked.
And also, the two gaskets that go on each side of the intercoooler.
If I were you, I would check first the gaskets. My 2011 has around the same miles as yours and the pipes are in very good shape. The gaskets might be done because time and also heat has destroyed them.
Please keep us updated if this worked for you also, so others can see.
Also, when you are datalogging, do it in 3rd gear and WOT from 2000-2500 rpm and right after you change to 4th stop the datalog. That's how we can see accurately what is going on on your car.

[Malteser_wfj]

Thanks for the reply minulache , I've gone ahead and ordered 3, 19, and 15 as well as the part you had listed 11.61.8.506.782 and they should be with me next week direct from BMW.

I'll try and log some more pulls this week and will be sure to do them in 3rd and go WOT sooner in the rpm range.

I think it's curious how my leak appears to start only at around 4700rpm. Or that's when the STFT start shooting into the negative.

Next up I'm going to replace the vacuum pipes over summer anyway -
11657588771
11657588773
11657605416

Thank you for all your help and I'm glad that it's fixed your leak!!

[Malteser_wfj]

Originally Posted by minulache

Today I changed the gaskets from the intercooler and from the turbo outlet to intercooler and now it's holding boost as it should for a PWG, so problem solved
Malteser_wfj , for the pressure sensor I used a gasket from a set, Inner diameter of 9mm and thickness of 2mm.
I did 15 and 29 from that diagram and also today I changed the turbo outlet to intercooler gasket with 11618506782, I couldn't find it in the diagram and just ordered this one to try and it worked.
And also, the two gaskets that go on each side of the intercoooler.
If I were you, I would check first the gaskets. My 2011 has around the same miles as yours and the pipes are in very good shape. The gaskets might be done because time and also heat has destroyed them.
Please keep us updated if this worked for you also, so others can see.
Also, when you are datalogging, do it in 3rd gear and WOT from 2000-2500 rpm and right after you change to 4th stop the datalog. That's how we can see accurately what is going on on your car.

Took some more logs today that should be better. 3rd gear starting at low rpm into 4th.

Car is going in on Tuesday next week so will update on any findings

https://datazap.me/u/lemansn55/log-1...og=0&data=4-20

https://datazap.me/u/lemansn55/log-1...og=0&data=4-20

My fuel pressure is dropping as the revs increase, is that normal or potentially a weak LPFP?

[minulache]

So, I noticed that now my boost is very good after all the changes BUT my WGDC hits 100%... any idea what I should look for? I think it's clear that there is no boost leak given the boost pressure now. Maybe the pressure converter or boost solenoid?

https://datazap.me/u/minulache/0906-...og=0&data=4-17

[minulache]

Fixed finally. Changed the boost solenoid/pressure converter and the boost is alot better. See log.

https://datazap.me/u/minulache/1906-1?log=0&data=4-5-17